Decimal point and zero printing mechanism for calculating machines



s. BEIKUFNER 3,455,504 DECIMAL POINT AND ZERO PRINTING MECHANISM FOR CALCULATING MACHINES Filed Aug. 14, 1967 July 15, I969 United States Patent Int. Cl. oosc 29/00 US. Cl. 235-6028 6 Claims ABSTRACT OF THE DISCLOSURE Printing mechanism for a calculating machine having printing hammers for the digits entered into the machine and printing members for decimal points which latter can be made singly effective or both ineffective; with an abutment arrangement which prevents all printing hammers above the highest digit entered into the machine from printing except when a printing member for a decimal point is made effective and in which case all printing hammers which print to the right of the decimal point and the one which prints immediately to the left thereof are released for printing regardless of the digits entered into the machine.

The present invention relates to a printing mechanism for calculating machines, especially of fully automatic four-species calculating machines which comprise a device adapted prior to the start of a calculating operation to be adjusted manually for printing a fixed comma or fixed point and in which the printing of the zeros on the left-hand side of a value is prevented by means of a living bridge formed by abutments and counter-abutments.

It has heretofore been known to provide calculating machines with a manually adjustable device for printing a fixed comma or fixed point. According to such a device, a comma key or period key is by means of a linkage provided in the machine and equipped with an adjusting knob moved into its effective position and is printed at the successive printing operation with the respective values.

It is furthermore known (Swiss Patent No. 392,941) to prevent the printing of all zeros on the left-hand side of all values by a living bridge which is formed by counter-abutments on the adjusting wheels of the key 'wheels and by abutments connected to the printing hammers of the respective next higher value digit. With this device, however, no comma or period printing is provided.

It is, therefore, an object of the present invention to provide a printing mechanism of the above mentioned calculating machine type with a device which for purposes of printing a numerical value with comma or period will automatically free the respective first printing space left of the adjusted comma or period also if it does not indicate any value.

It is a further object of this invention to provide a device as set forth in the preceding paragraph which is simple and inexpensive to manufacture and comprises a minimum of parts.

These and other objects and advantages of the invention will appear more clearly from the accompanying drawing showing an exploded perspective partial view of a printing device according to the invention.

According to the present invention, it is suggested to bring abutments into engagement with counter-abutments of the printing hammers provided on the left-hand side of comma or period keys or levers, said first mentioned abutments being firmly connected to control elements which are pivotally arranged on printing hammers of the respective next higher printing section and being adjustable into an ineffective position by a control linkage adapted to move the comma or period key levers into printing position. In this way, the respective printing hammer arranged left of a comma or period key is moved into effective position, and thus all key wheels located right of said printing hammer and representing no value will be freed for printing zeros.

Referring now to the drawing in detail, six printing hammers 2 of a printing mechanism known per se are pivotally supported by a shaft 1 stationarily arranged in a framework. The printing hammers 2 are locked in their basic or rest position by a blocking rail 5 against the thrust of springs 4 acting upon said printing hammers and having one end connected to a shaft 3 stationarily located in the frame. The said blocking rail 5 engages the noses -6 of the printing hammers 2 so as to block the same but is adapted to be moved upwardly to permit the printing of a value. Rotatably mounted on the printing hammers 2 are key wheels 7 which by means of adjusting wheels 8, 9, 10 are permanently operatively connected with value transfer racks 11 which are only partially shown in the drawing. For a precise adjustment of the key wheels 7, there are provided pa-wls 13 which, under the influence of springs 12, are adapted to engage the adjusting wheels 8.

The intermediate two printing hammers 2 have each pivotally mounted thereon a key lever 15, 15' respectively provided with a comma or period key 14, 14' for a possible comma or period printing. The levers 15, 15' are adapted, by means of springs 16 connected thereto and to the printing hammers 2, to be tilted in their printing position in which, as indicated by the key lever 15, they engage abutments 17 of the printing hammers 2. The key levers 15, 15' comprise arms 18, 18' which are engaged from below by pins 20, 20 laterally connected in levers 19, 19. Levers 19, 19 are in their turn pivotally mounted on a shaft 21 stationarily located in the frame and by means of springs 22 are held in their counterclockwise tilted position in which the pins 20, 20' engage the arms 18, 18 and move the key levers 15, '15 to their ineffective position. The drawing shows that key lever 15' in its ineffective position which is arranged on the fourth printing hammer 2 when counting from the left of the drawing. Between the two levers 19, 19', a control member 24 is provided on a shaft 23 having a square cross-section. At both sides of the control member 24 there is provided a control pin 25, 26' each, said control pins being offset with regard to each other 'by and In the illustrated position, the control pin 25 engages an arm 27 of lever 19 from below and maintains said arm in its tilted position against the thrust of spring 22. By rotating shaft 23, the control pin 25 again releases lever 19, and the control pin 26 eventually engages arm 27 of lever 19 and tilts the same in clockwise direction.

Shaft 23 has furthermore connected thereto a pinion 28 which through a rack 29 is coupled to a slide 30. Within the range of the key field, the slide 30 has an adjusting knob 31 which is adapted manually to be displaced into different positions by turning shaft 23, said positions being blocked by any standard blocking means not shown in the drawing. That side of the printing hammers 2 which faces the printing roller or paper strip is provided with ears 32 which serve as abutments and cooperate with counter-abutments 33 and form a known so-called living bridge. The said counter-abutments 33 are provided on entry wheels 9 of the respective next lower digit. As abutment for the highest digit there is provided an ear 34 connected to the machine frame. The counterabutments 33 are so arranged that they will occupy a blocking position behind the abutments 32 of the respective next higher printing hammers 2 when the key wheels 7 do not indicate a value or occupy zero position. In this instance, no value printing occurs after the printing hammers 2 have been released by the blocking rail 5.

As will furthermore be seen from the drawing, the printing hammers 2 carrying a comma or period key lever 15, represent an exception. The adjusting wheels 9 of these printing hammers 2 have counter-abutments 35 which are offset relative to the counter-abutments 33 by 180 but rotate in the same direction. These counterabutments 35 cooperate with abutments 36, 36 of the respective next higher digit in the same manner as described above and form the living bridge. The abutments 36, 36 form parts or angled off ears of control members 37, 37 pivotally arranged on the respective printing hammers 2 and are held in their blocking position by springs 38 engaging the control members 37, 37'. The control members 37, 37 are provided with control edges or cam surfaces 39, 39 engaged by pins 20, connected to levers 19, 19, said cam surfaces being adapted to tilt the control members 37, 37 in counter-clockwise direction to make the abutments 36, 36' ineffective. In their basic or rest position, all printing hammers 2 are blocked in their positions shown in the drawing, and the key wheels 7 do not indicate any value while the comma or period key levers 15, 15' are held in their ineffective position by levers 19, 19'. By introducing a value into a key Wheel 7, the counter-abutments 33, 35 provided on the adjusting wheel 9 pertaining thereto are moved into their ineffective position. With the subsequent printing operation, the blocking rail 5 is lifted upwardly, and the printing hammer 2 is freed which carries a value indicating key wheel 7. By the abutments of this printing hammer 2 and by the subsequent abutments 32, 36, 36', all printing hammers on the right-hand side of this section (on the lefthand side in the drawing) are released even when their key Wheels occupy zero position. The printing hammers 2 on the left-hand side of the respective digit (in the drawing on the right-hand side), however, remain blocked. With a value printing operation without comma or period, thus all zeros on the left-hand side of a value are not printed.

For a calculating operation in which a certain number of commas or periods is desired, this number has to be set prior to the start of the calculation by displacing the knob 31. As an example, shown in the drawing, it may be assumed that on the right side of a comma or period two value sections are desired. By displacing the slide 30 from its zero position by one indexing step, the control pin of the control member 24 moves into the illustrated position in which it tilts lever 19 in clockwise direction. As a result thereof, pin 20 frees the comma or period key lever 15 which, in view of spring 16, moves into printing position. At the same time, pin 20 engages the control edge or cam surfrace 39 of the control member 37 and tilts the same in counter-clockwise direction whereby the abutment 36 frees the respective counter-abutment 35 of the value section left of the comma or period. Thus, the printing mechanism has been adjusted.

If now, for instance, the printing of a value 15.16 is effected, the pro-setting effected by the slide remains ineffective because already the fourth printing hammer 2 (when seen from the left in the drawing) is freed by turning of its introducing wheel 9. If, however, the value to be printed is less than I, for instance 0.24 or 0.03, after releasing the printing hammers 2 by the blocking rail 5, the first printing hammer 2 left of the period (in the drawing on the right-hand side of the period) will at any rate also be printing because its counter-abutment was already released by abutment 36 prior to the start of the calculating operation. When printing values which are less than 1, therefore the value section left of the period is printed as zero."

By adjusting the slide 30 by a further indexing position, the control pin 25 of control member 24 frees the lever 19 while the control pin'26 engages the lever 19' and adjusts the printing mechanism as mentioned above to three value sections on the right-hand side of the period by tilting the key lever 15' into its printing position and moving the abutment 36' into its ineffective position.

It is, of course, to be understood that the present invention is, by no means, limited to the particular constmction shown in the drawing but also comprises any modifications within the scope of the appended claims.

What is claimed is:

1. A printing mechanism for a calculating machine, especially a fully automatic four-species calculating machine in which the machine comprises a plurality of printing hammers having key or digit wheels thereon, auxiliary printing members adjacent a selected intermediate adjacent pair of the printing hammers for printing periods or commas to serve as a decimal point, said printing hammers and printing members having a rest position and being moveable therefrom to carry out a printing operation, a fixed abutment adjacent the printing hammer pertaining to the leftward most or highest digit to be printed operable when the digit wheel of the said hammer is adjusted to Zero to prevent the hammer from moving into printing position, cooperating elements of abutment means on each printing hammer and the adjacent printing hammer which prints next .rightwardly thereof operable to prevent movement of any said adjacent printing hammer to printing position when the digit wheel thereon is adjusted to zero when a value is entered into the digit wheel of a printing hammer which prints to the left thereof, presettable means for making said auxiliary printing members selectively effective for printing or both ineffective for printing, and means operable upon making of either of said printing members effective to print a period or comma for making the said abutment means for the printing hammer that prints next leftwardly of the said effective printing member ineffective whereby also all printing hammers which print to the right side of said effective printing member will be released for printing whether or not a value is posted on the digit wheels thereof.

2. A printing mechanism according to claim 1 in which the abutment means for each printing hammer which prints immediately to the left of a said printing member comprises a first abutment element under the control of the digit wheel thereon and in effective position only when the digit wheel is adjusted to zero and a second abutment element moveably mounted on the printing hammer which prints immediately to the left, said second abutment element being normally in effective position and being moveable out of effective position, and means operated by said presettable means when moved into position for making one of said auxiliary printing members effective for pivoting the said second abutment element pertaining to the printing hammer next to the left of the said printing member into ineffective position.

3. A printing mechanism according to claim 2 in which each said second abutment element is pivoted on the respective supporting printing hammer and has a tonguelike projection thereon forming the portion which engages the pertaining first abutment element, a spring urging each second abutment element toward effective position, a cam surface on each said second abutment element, and said presettable means comprising rod-like members for engaging said cam surfaces to move said second abutment elements into ineffective position.

4. A printing mechanism according to claim 3 in which said auxiliary printing members are spring urged toward effective position, and said rod-like members being engageable With said members and moving them into ineffective position immediately upon disengaging from the respective said cam surface and vice versa.

5. A printing mechanism according to claim 4 in which tiltable levers are provided on which said rod-like members are mounted, and springs normally holding said levers to such position that said rod-like members engage their respective auxiliary printing members and hold the said auxiliary printing members in ineffective position.

6. A printing mechanism according to claim 5 in which said presettable means includes a tiltable shaft, and circumferentially spaced control pins carried by said shaft so arranged thereon that upon rotation of said shaft first one and then the other of said control pins engages a respective one of said tiltable levers and moves the pertaining tiltable lever into position such that its rod-like member releases the respective auxiliary printing member to effective position while simultaneously engaging the cam surface of the respective second abutment means pertaining thereto so as to move the said respective second abutment means into ineffective position.

References Cited UNITED STATES PATENTS 11/ 1949 Mehan 235-60.28 8/ 1962 Wagemann 101-93 10/ 1962 Wagemann 235*60 3/1963 Gelling 235-60.15

10/1963 Chall et a1. 101-93 12/1965 Gelling 101--93 7/1966 Gassino 235-60.25

US. Cl. X.R. 

